1. Field of the Invention
The process of the present invention constitutes a means for the reactive separation of hydrolyzable polymers such as polyethylene terephthalate resins ("PET"), polyamides, polycarbonates, polyethers, poly-acrylonitriles in mixtures with polyolefins such as polypropylene ("PP") and polyethylene ("PE") by selectively converting the hydrolyzable polymers to their starting materials, e.g., PET to terephthalic acid ("TPA") and ethylene glycol ("EG"). Selective conversion is carried out by heating the starting mixture of neutral liquid water, hydrolyzable polymers, preferably PET, polyamides, polycarbonates, polyethers and polyacrylonitriles, and other non-hydrolyzable polyolefins such as PP and PE at from about 200.degree. C. up to the critical temperature of water, which is about 374.degree. C. at autogenous pressure.
2. Discussion of Related Art
The hydrolysis of high molecular weight condensation polymers such as PET in the absence of added acids or bases, is well known in the art. When, for example the condensation polymer is PET, the primary hydrolysis products are TPA and EG, see, e.g., U.S. Pat. No. 4,578,510, U.S. Pat. No. 4,605,762, U.S. Pat. No. 4,620,032 and U.S. Pat. No. 3,120,561. However, the art does not teach nor suggest a process for the reactive separation of condensation polymers such as PET, polyamides, polycarbonates, polyethers, polyvinylchlorides, and polyacrylonitriles from mixtures containing other polymer resins by hydrolyzing the condensation polymer into its water-soluble components in the presence of neutral liquid water as a starting material in the absence of any externally supplied acids or bases and at autogenous pressure.